Designed to accurately indicate when a chain reaches .5% and .75% which most chain manufactures recommend replacement. Chain wear indicator is a simple go or no go tool. - Updated to be longer, more accurate and features permanent measurement markings - Accurately indicates when a chain reaches 0.5% and 0.75%, the points at which most chain manufacturers suggest replacementSpecification:-- keyword search: CC-3.2 , park consumer tool , CC3.2